The present invention relates to air bags and more particularly to a new construction of the air bags.
Historically air bags have been made by sewing woven fabric together. Depending upon the use of the air bag the woven material might have been coated with material such as silicon or urethane. In order to control of the extension and shape of the air bag many airbags include tethers. For example, the prior art shows an air bag in which the inner panel and outer panel of material are separated by a plurality of tethers. When the air bag is inflated, the inner and outer panels are separated by the length of the tethers. This type of construction has benefits in that the occupant's body, which is typically adjacent the inner panel of material, is maintained a further distance away from the side of the vehicle, which is typically adjacent the outer air bag panel. This type of construction is easily achieved when the various parts of the air bag are sewn together.
The prior art also illustrates air bags can be made by rf (radio frequency) welding various panels of material together or by weaving yarn utilizing a special loom and head, such as a Jacquard head. Dobby looms can also be used to make a functionally similar air bag. As used herein a woven bag is also referred to as a one-piece-woven bag.
One of the issues with the rf (radio frequency) and woven types of air bag construction is that the interior or inner panel and the outer or exterior panel of the air bag are joined together (along a woven or bonded seam). Consequently, in an accident if the occupant hits the air bag in the region of the seam, the occupant might impact the vehicle side (which is adjacent to the outer panel).
It is an object of the present invention to provide an air bag that can be constructed utilizing rf (radio frequency) or woven technologies while still being able to easily include internal tethers.
The invention also relates to a one-piece, integral woven tube or cover into which an elongated, folded curtain air bag can be inserted and stored.
Accordingly the invention comprises: a method of forming an air bag comprising the steps of: a) partially constructing the air bag and leaving an opening at a determinable location at or near the periphery of the partially constructed air bag to provide access to the interior thereof; b) inserting one or more tethers into the interior of the bag through the opening; c) securing one side of each tether to a first panel of the air bag and then securing a second side of the tether to a second panel of the air bag; and d) closing the opening. The invention also includes: a curtain air bag comprising: opposing panels of material joined at a periphery of the air bag along a peripheral seam that substantially extends about the periphery of the air bag, the peripheral seam being open along a determinable length to provide access to the interior of the air bag; a tether having a determinable size, placed within the interior of the air bag through the access opening and having generally opposing first and second sides, the first tether side secured to a first of the air bag panels and a second tether side secured to a second of the air bag panels; and a peripheral seam segment for closing the open portion of the peripheral seam after the tether is secured in place. A final embodiment the invention includes a tubular cover for a folded curtain air bag. The woven cover includes a tear seam, which is integrally formed during the weaving process.
Many other objects and purposes of the invention will be clear from the following detailed description of the drawings.